Problem: $ { \left[\begin{array}{rrr}{4} & {1} & {2} \\ {3} & {2} & {0}\end{array}\right]-\left[\begin{array}{rrr}{0} & {1} & {0} \\ {2} & {4} & {3}\end{array}\right] = {?} } $
Solution: To find the difference of two matrices, subtract the corresponding items between each matrix. ${\left[\begin{array}{rrr}{4}-{0} & {1}-{1} & {2}-{0} \\ {3}-{2} & {2}-{4} & {0}-{3}\end{array}\right]}$ Now, simplify: ${\left[\begin{array}{rrr}{4} & {0} & {2} \\ {1} & {-2} & {-3}\end{array}\right]}$